Location
Irradiation
Irradiation refers to the exposure of solar panels to sunlight, measured in terms of solar energy per unit area. Understanding and optimizing irradiation levels are crucial for maximizing energy production and efficiency in solar power systems.
Global Horizontal Irradiance (GHI)
GHI is the total solar irradiance received per unit area on a horizontal surface, including direct and diffuse sunlight. It is a key parameter for PV power plants, as it accounts for all sunlight incident on a horizontal plane.
Direct Normal Irradiance (DNI)
DNI is the amount of solar radiation received per unit area by a surface perpendicular to the sun's rays on a plane at the Earth's surface.
Diffuse Horizontal Irradiance (DHI)
DHI is the component of solar irradiance that reaches a surface after scattering due to atmospheric conditions. It represents the diffuse or scattered sunlight and contributes to overall energy generation in PV systems.
Global incidence
Global incidence refers to the total solar radiation received on a surface, typically measured in kilowatt-hours per square meter (kWh/m²) or watts per square meter (W/m²). It accounts for both direct sunlight and diffuse sunlight that reaches the solar panels.
Design temperature
Under standard test conditions (STC), the reference cell temperature is 25 degrees Celsius. Cell temperature affects performance and is dependent on factors such as ambient temperature, isolation technology and wind.
Generally, as temperature increases, the efficiency of PV cells decreases. If the cell temperature is below 25 degrees (which is the reference temperature in STC), the cell performance will increase.
Albedo
Albedo refers to the measure of how reflective the ground surface is to sunlight. It represents the fraction of solar radiation that is reflected back into the atmosphere rather than being absorbed by the surface. Surfaces with higher albedo, such as snow or grass, reflect more sunlight, which can indirectly increase the efficiency of nearby solar panels by providing additional irradiance. Conversely, surfaces with lower albedo, such as dark asphalt or soil, absorb more sunlight.
Albedo value is important when using bifacial modules, as they can absorb irradiance from the rear side of the module as well.
Topography
Topography involves the physical features and layout of the land, influencing the arrangement of solar panels and the overall design of the system.
Slope analysis
Slope analysis refers to the assessment of the terrain's incline or gradient to determine its suitability for installing solar panels. This analysis involves evaluating the angle or steepness of the land where solar panels will be installed to optimize their orientation for maximum sunlight exposure.
Additional resources
For more information on configuring your PV settings in Glint Solar, see Adjusting the PV settings
Learn more about the technical concepts described above in the Solar Site Planning Guide: